Truck



I 1942- R. B. COTTRELL 2,306,396

TRUCK Filed April 12,1940 4 Sheets-Sheet 1 h INVENTOR.

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Dec. 29, 1942. R. B. COTTRELL TRUCK Filed April 12, 1940 4 Sheets-Sheet 2 IIIIIIIII! naivilll'l IIIIIIIIIIIII'IIIIIII1!!v Dec. 29, 1942. R. B. COTTRELL 2,306,396

' TRUCK Filed April 12, 1940 4 Sheets-Sheet 3 INVENTOR. fioberifi Cow/"6Z6,

of purposes.

Patented Dec. 29, 1942 UNITED STATES 'PATEN moon Robert B. Cottrell, Chicago, 11]., assignmto American Steel Foundries, Chicago, 111., a corporation of New Jersey Application April 12, 1940, Serial No. 329.233

15 Claims. (01. 267-9) My invention relates to a railway car truck, and more particularly to a novel spring arrangement therefor functioning as a means of retaining the parts of the truck in square relationship with one another.

In railway freight cars many forms of snubhers have heretofore been used and for a variety It is an object of my invention to combine a friction absorbing device or snubber with coil springs and with other parts of a railway car truck, particularly a side frame and bolster, to accomplish in novel manner new and the side frame members on which the load carry- 'ing member is normally supported.

A diiferent object of my invention is such a.v

combination of coil springs and friction absorbing devices in a railway car truck as will provide a means of tying and squaring the bolster with respect to the side frame, and as a result will also tend to prevent fnosing, that is, longitudinal displacement of the side frames with respect to each other in such a truck as here contemplated.

Anothe object of my novel arrangement is such a constructed relationship between the spring unit and the truck parts as will enable the said spring unit to act as a resilient means for restoring the truck parts to a square relationship when for any reason they are thrown out of square.

A diflerent object of my invention is to design a novel spring arrangement in a railway freightcar truck which will compel the friction absorbing devices and the coil springs to operate substantially in unison, thereby securing maximum eiliciency of the spring group or the spring unit.

Still another object oi my invention is a com bination of coil springs and friction devices in a'railway car truck so arranged as to provide resistance to relative horizontal movement of side frame and bolster. v

My novel arrangement also contemplates a preassembled spring group arrangement which affordsi a relatively soft ride by permitting the use therein of a longer travel spring than could otherwise be used in the available vertical height. My invention contemplates such an arrangement as will prevent-either the coil springs or the friction absorbing device from operating independently ofeach other, and thereby produces maximum eillciency of the supporting group as a unit. I accomplish this by fixing the followers of the friction device to the spring plates or spring seats between which the load supporting springs are seated so that the springs and the friction device operate in unison, the springs assist in opening the'friction device, and the friction device resists the spring movement on both compression and release. The amount-of resistance ofiered in each direction willdepend upon the character of the friction surfaces.

It will readily be understood by those skilled in a the art that in high speed operations such as is demanded by modern freight car trucks, the impacts are of very high velocity, and repeatedlyit has been demonstrated that manyfriction absorbing devices do not react fast enough under release to be fully operative when the succeed ing blow or impact is received under such conditions. .My novel arrangement compels the springs and the snubbing device to operate as a unit and insures the full opening of the snubber unit to the maximum permitted by the spring reaction. .1

The most common form of freight car truck up until the last few years consisted of two side frames and a .transversal load-carrying member or bolster, together with a so-called spring plants which served as a means of securing the side frames in square relationship with one another, thus holding square all the truck parts. The bolster was usually supported on aspring group at each end and if properly mounted had no function as a squaring'member. Recently the so-called spring plankless four wheel truck had been developed, wherein the structural parts of the truck comprise simply the two side frames and the bolster resiliently supported thereon in rangement, a clearance is provided between the co-operating column portions of the sideframe and bolster as the bolster moves up and down on the spring group when in service, resulting in changes in vertical relationship between these two members' This clearance also permits limited horizontal motion or relative movement between the bolster and side frame, allowing out of-squareness of the-truck, angling of side frames,

longitudinal movement of; frames with respect to each other and to the bolster, or a combination of the above. Such move'fiiie- Fis resisted by the springs but such resistance under empty car or light loads as coil springs have very little lateral stability when freeor only slightly compressed.

My invention contemplates such an arrangement of a spring plankless car truck as will substantially increase the resistance against horizontal instability as will be clearly apparent to those skilled in the art from further consideration of drawings and descriptive material herein presented. I

In the drawings Figure 1 is a fragmentary side elevation of a four wheel car truck embodying my invention.

Figure 2 is a sectional view thereof taken substantially in the plane indicated oy the line 2-2 of Figure 1, with the bolster shown in side elevation and partly cut away to show more clearly the form of engagement with the spring group.

parable to Figure 12, showing a method of mounting the friction absorbing device between the side frame and bolster, and wherein the parts are disposed in normal relationship, one with another.

Figure 2A is a fragmentary view corresponding in general to that of Figure 2 and showing an alternate method of interlocking the bolster with the spring group.

Figure 3 is a top plan view of the structure shown in Figures 1 and 2, with the top member of the side frame cut away and the bolster omitted.

Figure 4 is a side elevation corresponding generally to Figure 1, and illustrating an optional arrangement of the spring unit.

Figure 5 is a fragmentary sectional view corre sponding generally to that of Figure 2, showing a method of securing a friction absorbing device in the spring group and the position of the parts therein when the truck members are in normal position with respect to one another.

structed in accordance with my invention, showing the relative position of the top and bottom spring plates and snubber followers when torsion is applied as a result of an out-of-square condition between side frame and bolster. I

Figure 8 is a'more or less diagrammatic illustration of the friction absorbing device shown in Figure 15 is a view similar to view 14, showing the distorted position assumed by the parts when the bolster-moves laterally with respect to the side frame. Y

Figure 16 is a view comparable to Figure 15, but shows the relative position assumed by the parts under conditions similar to those in Figure 15, wherein, however, the friction absorbing device ismounted in the heretofore practiced manner instead of being restricted in its movements relative to the supported and the supporting members.

Figure 17 is a diagrammatic sketch comparable to those of Figures 8 and 9, showing the relative position assumed by the snubber parts under conditions illustrated in Figure '7.

Describing in greater detail the structures illustrated, and referring first to the modification shown in Figures 1 to 4 inclusive, a well-known form of four wheel railway freight car truck wherein the trunk frame generally designated 2 comprises the compression member,| and a tensionmember 8 integrally joined by spaced guide columns 8, 8, said columns forming with said tension and compression members the usual bolster opening Ill. Along upper surfaces of the columns, the opening is narrowed somewhat to flanges l6, l8 and the inner guide flanges i8, ll

of usual form; The tension member 6 is of box section below the spring seat 20, and the top chord 22 is widened to accommodate my novel spring group generally indicated at 24. The

my novel arrangement when the parts are in normal position with respect to one another.

Figure 9 is a view comparable to Figure 8,

showing the relationship which the parts of the friction absorbing device assume .under conditions such as illustrated in Figure 6. Y

Figure 10 is a sectional view comparable to Figures 5 and. 6, showing the condition which prevails with respect to such a friction absorbing device as that illustrated when said device is mounted under heretofore prevailing conditions.

free to rock-within limits between the supporting member and the supported member.

Figure 11 shows another embodiment of my invention and comprises a fragmentary side elevation of a four-wheel truck.

Figure 12 is a sectional view of the truck structure shown in Figure 11, the section being taken substantially in the vertical plane bisecting the truck transversely as indicated by the line l2-l2 of Figure 11. v Figure 12A is a fragmentary view corresponding in general to that of Figure 12 and showing plate 26, the top spring plate 28, each of the said spring plates being flanged around a major portion of its perimeter to securely enclose the spring group parts, and'a group of coil springs 30, 30 arranged adjacent the four corners of the group and spaced laterally of the truck to accommodate the snubbing device 32. The top and bottom spring plates are aflorded positioning lugs as at 34., which are received in recesses formed on the spring seat 20 and in the bottom wall of the bolster for that purpose. The bolster is also formed with downwardly projecting lugs 36, 38 adjacent the inboard and outboard edges of the top spring plate as a further means of positioning the bolster with respect to the spring group.

55 To still further stabilize the spring group with respect to the side frame, the spring seat 20 is afforded upstanding lugs 38, I8 which are received' in corresponding openings formed in the bottom spring plate. If desired, positioning lugs 39, 39 (Figure 2A) may be integrally formed on the bolster l4 and received in corresponding openings in the top spring plate 28, thus affording additional means of preventing relative displacement therebetween. v

The spring group contemplates an arrangement wherein the top follower 40 of the snubber shall be secured in any convenient manner to the top spring plate 28, and the identical bottom folparts of the snubber is the retaining means oryoke 46, and between the respective ends of said yoke and the wedges at opposite sides of the device are the compressed resilient pad 48, 48. The snubber followers 40, 40 and the side wedges 44, 44 are interlocked with respect to each other to hold the parts in assembled relationship, and

3 tive spring groups, but the side wedges ll, 44 of the snubber assume diagonal positions with respect to the followers, producing the condition along the complementary diagonally arranged friction surfaces of the wedges and followers illustrated at 58, 58 (Figure 9). This distortion of the parts of the snubber compresses the rubber pads 48, 48, as shown in Figure 9. and thus a the said interlocking means limit the expansion of the device.

Inasmuch as the said top and bottom followers 40, 40 are secured to the top and bottom spring plate in assembly, the snubber thus acts as a means of limiting the expansion ofthe coil springs which are associated'with the snubber-in the spring group. By virtue of this feature I may make use of coil springs having a relatively long travel as compared with coil springs which might be used in a similar vertical space where. no restriction other than the superposed load is imposed upon the expansion of other words, I may use a spring having a free height such as indicated at 50 (Figure 4), with the said spring compressed after assembly to the position shown at 52.

the coil springs. In"

Such a spring oifers less resistance per unit of travel'and is sometimes described as a relatively soft reacting or low rate spring in comparison with a spring of normal length for such a vertical opening as contemplated. To those skilled in the art, it will readily be apparent that the use of such coils having a greater free height in a confined spring group such as that I have described will give a relatively softer reaction as compared with that which would be received from a similar spring group using coils which had a lesser free height and were not under precompression, but were designed at the same time to operate in a corresponding vertical space within similar travel limits. Such an arrangement is illustrated in Figure 4, wherein the free height of the coils is indicated at X and the assembled height thereof is indicated at Y, the difference representing the amount of precompression of the relatively soft coil springs 52, 52.

In Figure 5, I have illustrated one method of securing the top and bottom snubber followers 40, 40 to the respective spring plates of the spring. group as by welding, indicated at 5!, 54. It will be understood that other securing means such as bolts might be used or the snubber followers and the spring plates may be cast integral.

In Figure 5, I have. shown the relative position of the parts when the bolster superposed on the top spring plate 28 and the side frame supporting the bottom spring plate 26 are in normal position with respect to one another. Figure 6 illustrates the condition which prevails when the bolster moves laterally with respect to the side frame as indicated by the arrows 56, 56. Under such conditions the top' and bottom snubber followers 40, 40 are compelled to move .with the respective rotation is indicated by arrows .dition illustrated in Figure 17.

with respect to the other side frame. In such a movement, the bolster becomes out of square with respect to one or both side frames and such a condition develops as is illustrated in Figure 7, wherein it maybe noted that the top spring plate 28 has rotated an appreciable amount with respect to the bottom spring plate .26. The relaat B0, 80. The top and bottom snubber followers 40, I0, fixed to the respective spring plates, likewise rotate with respect to each other and this produces the con- Such a distorted arrangement of the snubber parts compresses the rubber pads 48, 48 and thus sets up energy in the snubber to restore the parts to their normal position, and so tends to. prevent said "nosing action and to restore said side frame and bolster to their normal relative positions.

In contrast to the showing in Figure 6 is that of Figure 10, wherein may be seen the usual normal arrangement of the spring group between the supporting spring seat 20 of the side frame and the bolster which is superposed on the top spring plate 28 and positioned with respect thereto. Likewise the bottom spring plate 26 is positioned with respect to the spring seat 2e. Under such conditions this spring group may be assembled in any well-known manner with the usual coil springs surrounding the snubber. 1 However, as heretofore practiced, the top and bottom followers of snubbers have been formed with somewhat arcuate seats as indicated at 62, 62, to permit the said followers to rock with respect to the spring plates when such lateral motion as that already described takes place between the side frame and bolster and thus causes relative lateral displacement of the top and bottom spring plates. The action of the snubber under such a conventional arrangement is illustrated in Figure 10. When lateral movement of the side frame and bolster occurs as illustrated by thearrows 64, 64, the rocking action of the snubberrt'i is indicated by the arrows '66, 86, and this rocking action permits the'parts of the snubber, particularly the followers and side wedges, to retain their normal positions with respect to one another so that there is no distortion. Under these conditions the snubber is unable to-function as a means of restoring the parts to normal although the coil springs, of course, have some lateral stability. v

In spring group arrangements such as I have illustrated, the ability of the snubbing device to function as a squaring means is proportional. to the length ofthe moment arm afforded therein. In other words, it is desirable when the snubber is so functioning, to have the displaced parts of the snubber as far as possible within practical limits from the center flange II8 received in a complementary Y and if desired may known form in which the of turning. Such a center of rotation is illustrated at (Figure '1) and at I0 (Figure 1'1). For this reason I have illustratcd a device wherein the snubber is shown as a relatively long rording a maximum length of moment arm effective to return the parts to their normal relationship. While I have illustrated a particular form of snubbing device, other snubbers might be adapted to perform this function.

In the modification shown in Figures 11 to 13 inclusive, 1 have shown my to another well-known form of four wheel railway car truck wherein the side frame generally indicated I02 comprises I04, a tension member- I00 and he integral column I00 forming therewith a bolster opening IIO into which projects the end of the bolster II2. Said bolster end is formed with top lateral shelves I I4 in engagement with the column guide face I I0 of well-known form, said face beinginter'rupted centrally thereof by the vertical guide Associated with the bolster end I serving as additional in the shelf "I I4. is the insert. member means of interlocking said insert I20 having column guide surfaces and narrow structure thus af- 3 the compression member V the bolster and side frame,.

I40, I44 is well illustrated in Figures 14 and 16,

, the said interlocking means comprising a wellinvention as applied slot II! similar to those on the shelf II4 of the bolster,

and likewise having engagement of the column guide surfaces H0 and the guide flange H0 in this well-known form of truck. The horizontal portion of the insert I20 is received in a' transverse slot at the bottom wall of the bolster, and after assembly may be interlocked therewith as at I22 so that the bolster and insert member operate as a unit. Supporting the bolster end is a spring group generally indicated at I24 similar to that of the previous modification and cominterposed snubber generally prising a group of coil-springs I20, I20 with the t designated I20, said.

in the previous modification and comprising top and bottom followers I40, I40, side wedges I44, I44, retaining means I40, I43 at opposite ends of the device. In this modification a top spring plate I30 is shown interlocked with the bolster as by means of the downwardly projecting lugs I32, I32 on said bolster, be further interlocked with the spring group by means of the downwardly projecting lugs I34, I34 (Figure 12A) which may project through aligned openings in the top spring plate I30 and the top snubber follower I40. This modification contemplates an arrangement wherein the snubber followers shall be respectively secured to the top spring plate I30 and to the spring seat I33 of the side frame as by means of welding, such as indicated at I30, I35 (Figure .14), or by any other convenient means whereby the snubber is so secured between the supporting and supported members as to operate as a means limiting the vertical travel of the spring group as a whole and in restraint of other relative movements between said members.

In this modification, the side frame is of welltension member below the opening member H0 is widened to form a spring seat I33 with thelateral edges of said seat formedwith upstanding flanges I30, I30 serving as confining means for the spring group, said tension member below said spring seat beand resilient pads I40,

.will thus be clearly seen known arrangement wherein a vertical slot I00 centrally formed on each side wedge I44 receives at each end thereof a follower lug I02. The cooperation of said lugs with the-shoulders at the ends of said slots afford a means of limiting the vertical opening of thesnubber and of retaining the parts in normal assembled relationship. It

that with the parts constructed as described, the spring group will be confined between the spring seat of the side frame and the top spring plate with the snubber followers secured respectively to said side frame spring seat and said top spring plate thus serving as a means of limiting the vertical spread therebetween. v

In addition, the sun ber serves as a stabilizing and squaring means for the relatively moveabie side frame and bolster by being interlocked with the top spring plate as already described while the side frame is securely fastened to the bottom follower of the snubber in any convenient manner. Under those conditions, if the bolster moves laterally with respect to the side frame, as indicated by the arrows "4,104 (Figure 15), the snubber is forced into the distorted form illustrated, wherein the resilient pads I40, I40 are compressed and energy is set up which serves to more or less diagrammatically iilustratedin Fig. .17, wherein again the resilient pads are compressed and energy is stored up effective to return the parts to their normal positions.

' Figure 16 illustrates the conditions which would prevail if the snubber and spring group were mounted in the conventional-manner with the coil springs and snubber independently confined-between the top spring plate I30 and the spring seat I32 with no restraint imposed upon the top and bottom followers of the snubber to prevent a rocking action. On the contrary, in

ing of box section as illustrated in Figure 12 with a center reinforcing rib I30. The manner in which the followers I40, I40 of the snubber are interlocked with the side wedges such conventional arrangements the snubber followerssare formed with more or less arcuate top and bottom faces as indicated at I02, I02 thus facilitating the rocking action of the snubber and permitting the snubber parts to remain in normal relationship one with. another when the top spring plate moves laterally under the bolster. with respect to the side frame as indicated by the arrows I04, I04. Under such conditions, the snubber I20 simply rocks on the said arcuate bases as indicated by the arrows I00, I00, and it 'does not function as a means of restoring the truck parts to their normal positions.

To those skilled in the art, it will be clear that in my novel arrangement I have a means of assembling the supporting and the supported membars in a railway car truck with a composite spring group of novel form so that the elements of said composite spring group are compelled to function as a unit and as such unit to serve as means of restricting the relative lateral motion of said supporting and supported members as well as means of restricting torsional movement therebetween.

Also my invention contemplates as above described, such an arrangement wherein thesprings associated with the friction absorbing device in the composite spring group may be precompressed as desired to afford a relatively soft spring action within the travel limits specified where said springs must aiford a specified lifting capacity.

It is to be understood that I do not wish to be limited by the exact embodiments of the device shown which are merely by way of illustration and not limitation as various and other forms of the device will, of course, be apparent to those skilled in the art without departing from the spirit of the invention or the scope of the claims.

I claim: I

1. In a railway car truck, a supporting member, a supported member, a spring group between said members, said members being capable of relative longitudinal, lateral and rotational movement, said spring group comprising a friction device with opposed followers rigidly secured one with respect including means for resiliently and frictionally restraining said followers against longitudinal, lateral and torsional movement with respect to each other.

2. In a railway car truck, a supporting member, a supported member, a spring group between said members, said members being capable of relative rotational movement, said spring group comprising a friction device with opposed followers rigidly secured one with respect to each of said members and including means for resiliently and frictionally restraining said followers against torsional movement with respect to each other.

3. In a railway car truck, a supporting member, a supported member, a'spring group between said members, said members being capable of relative longitudinal and lateral movement, said spring group comprising friction devices with opposed followers rigidly secured one with respect to each of said members and including means for resiliently and frictionally restraining said followers against longitudinal and lateral movement with respect to each other. V

4. In a railway car truck, a supporting member, a supported member, a spring group between said members, said members being capable of relative longitudinal, lateral and rotational movement, said spring group comprising a coil spring and a friction device with opposed followers rigidly secured one with respect to each of said members and including means for resiliently and frictionally restraining said followers against longitudinal, lateral and torsional movement with respect to each other.

5. In a railway car truck, a supporting member, a supported member, a spring group between said members, said members being capable of.

relative longitudinal, lateral and torsional movement, said spring group comprising a plurality of coil springs and a friction device interposed means for resiliently and frictionally restraining said followers against longitudinal, lateral and torsional movement with respect to each other.

and a coil spring having a free height substanto each of said members and therebetween with opposed followers rigidly secured one with respect to each of said'members and including means for resiliently and frictionally restraining said followers aga ir'ist longitudinal. lateral and torsional movement with respect toeach other.

6. In a railway car truck, a supporting member, a supported member, a spring group between said members, said members being capable of tional movement,

tially greater than the expanded height of said device, said device having opposed followers rigidly secured one with respect to each of said members and including means for resiliently and frictionally restraining 'said followers against longitudinal, lateral and torsional movement with respect to each other.

8. In a railway car truck, a supporting member, a supported member, a spring group between said members, said members being capable of relative longitudinal, lateral and rotational movement, said spring group comprising a friction device and a coil spring having a free height substantially greater than the expanded height of said device, said device having opposed followers rigidly secured one with respect to each of said members and including means for resiliently and frictionally restraining said followers against longitudinal, lateral and torsional movement with respect to each other, said means including side wedges interlocked with said followers to limit the expanded height of. said device.

9. In a railway car truck, a .supporting member, a supported member, a spring group between said members, said members being capable of relativelongitudinal, lateral and rotational movement, said spring group comprising a friction device and a coil spring having a free height substantially greater than the expanded height of said device, said device having opposed followers rigidly secured one with respect to each of said members and including means for resiliently and frictionally restraining said followers against loni gitudinal, lateral and torsional movement with respect to each other, said means comprising side wedges affording fulcrums for said followers.

10. In a railway cartruck, a spring arrangement comprising a supporting member, a top spring plate, a spring group between said member and said plate, said plate and said member being capable of relative longitudinal, lateral and rotasaid spring group comprising a coil spring and a spaced friction device with opposed followers rigidly secured one with respect to said member and the other with respect to said plate, said device including means for resiliently and frictionally restraining said followers against longitudinal, lateral and torsional movement with respect to each other.

11. In a railway car truck having a supporting and a supported member capable of relative ionand rotational movement, a

' sional movement with respect to each other, and

relative longitudinal, lateral and rotational movement, said spring group comprising a vertical coil spring and a spaced friction device, said device having opposed followers rigidly s'ecured one with respect to each of said members and including said plates being associated with said members respectively to resistlsaid relative longitudinal, lateral and rotational movement.

12. In a railway car truck, a spring arrangement comprising top and bottom plates capable of relative longitudinal, lateral and rotational movement, said arrangement comprising a friction device with opposed followers rigidly secured one with'respect to each of said plates, and including means for resiliently and frictionallv restraining said followers against longitudinal, lateral and torsional movement with respect to each other.

13. In a railway car truck, a spring arrangement comprising top and bottom plates capable of relative longitudinal, lateral and rotational movement, said spring arrangement comprising a coil spring and a spaced friction device with opposed followers rigidly secured one with respect to each of said plates, and including means for resiliently and frictionally restraining said followers against longitudinal, lateral and torsional movement with respect to each other.

14. In a railway car truck, a spring arrangement comprising top and bottom plates capable of relative longitudinal, lateral and rotational movement, said arrangement comprising spaced coil springs and an intervening friction device with opposed followers rigidly secured one with respect to each of said plates and including means for resiliently and frictionaliy restraining said followers against longitudinal, lateral and torsional movement with respect to each other.

15. In a railway car truck, a spring arrangement comprising top and bottom plates capable of relative longitudinal, lateral and rotational movement, said arrangement comprising a friction device and a coil spring having a free height substantially greater than the expanded height of said device, said device having opposed followers rigidly secured one with respect to each of said plates and including means for resiliently and frictionally restraining said followers against longitudinal, lateral and torsional movement with respect to each other.

ROBERT B. CO'I'IRELL. 

